1. Field of the Invention
The present invention relates to an apparatus and a method for ink jet recording, which perform recording on a recording medium by discharging ink. More specifically, the invention relates to an ink jet recording apparatus and a method for performing ink jet recording, which can perform recording on the full surface of the recording medium without any blank spaces.
2. Related Background Art
Conventionally, since recording operated only in a range completely coincident with the full surface of a recording sheet was not practical because of a form error of the recording sheet, a shortage of recording sheet conveying accuracy in the recording apparatus side, etc., the recording operation was normally started from a place inside by a predetermined distance from the end of the recording sheet. Accordingly, the result of recording usually had spaces (margins) of no recording along the end of the sheet.
However, as shown in printing services of silver salt photography, there are many who prefer a recording result of no blank spaces (no margins) and, in the ink jet recording apparatus, some means have been put to practical use for performing recording on the full surface of the recording sheet, on which recording has already been made, without any blank spaces. Such means are largely divided into a method of processing the recording sheet after recording, and a method of compensating for the above-described error or shortage of accuracy by performing a recording operation in a range exceeding an area of the recording sheet.
As one of the former examples, a method has been available, which obtains a desired recording result by providing a region surrounded with a perforated line, and an extra portion outside this region, to be cut off along the perforated line, on the recording sheet, performing recording not only in the region surrounded with the perforated line but also even in this extra portion, and cutting off the extra portion after the end of the recording operation. An example is shown in FIG. 31. On a recording sheet 13 including a recording region 53 formed by four perforated lines 52, recording is carried out in a region exceeding the recording region 53. After the end of recording, however, extra portions outside the recording region 53 are removed along the perforated lines 52. Thus, the result of recording on the recording sheet has no blank spaces (recording without margins) after the removal of the extra portions.
As disclosed in Japanese Patent Application Laid-Open No. 11-321016, there is a method of obtaining a desired recording result by performing recording on long roll paper, and cutting off only recorded portions after the end of the recording operation.
As one of the latter examples, regarding a recording operation performed in a range exceeding an area of the recording sheet, in order to prevent the staining of the backside of the recording sheet by ink directly discharged to a platen for holding the recording sheet, an apparatus has been put to practical use, which directly holds only the backside of the recording sheet with the platen hidden when recording is performed on a leading end or a rear end of the recording sheet.
In addition, as shown in FIG. 32, a method has been presented, which obtains a desired recording result by providing a recording sheet supporting member 50 movable in a direction similar to the scanning direction of a recording head 10, moving the recording sheet supporting member 50 while detecting a width of a recording sheet 13 by recording sheet detecting means 51, and executing recording of one line by dividing it into a plurality of portions.
In the foregoing conventional examples, however, some constraints have been imposed on the execution of recording on the full surface of the recording sheet without any blank spaces.
Specifically, in the case of the method of processing the recording sheet after recording, it is necessary to use a recording sheet having a size larger than that of the recording sheet obtained after the recording, and the recording apparatus itself must deal with such a size. Consequently, the enlargement of the recording apparatus has been inevitable. The user must process the recording sheet himself, accordingly complicating the operation. In addition, in the case of the method of manually removing the extra portions of the recording sheet along the perforated line, cut surfaces are not neatly aligned, resulting in a finishing problem.
In the case of the method of cutting the long roll paper after recording thereon, it is necessary to provide cutting means in the recording apparatus, resulting in increases in the size and costs of the recording apparatus. In the case of the method, in which the user cuts the long roll paper after continuous image recording thereon, it is difficult to cut the paper without any shifting at an image boundary, complicating the operation.
Furthermore, in the method of performing a recording operation in a range exceeding an area of the recording sheet, it is necessary to provide a mechanism for moving the platen in synchronization with the conveyance of the recording sheet or a mechanism for moving the platen in synchronization with the movement of a carriage. Consequently, complication and enlargement of the apparatus, and a cost increase have been inevitable.
The present invention was made to solve the foregoing problems inherent in the conventional art, and it is an object of the invention to provide an ink jet recording apparatus capable of performing recording on the full surface of a recording sheet without any blank spaces, and improving recording sheet finishing, and operability, without complicating or enlarging the recording apparatus, and without any cost increases.
Other objects of the invention are to provide an apparatus and a method for ink jet recording, which provide a rib row including a plurality of ribs in a direction intersecting the conveying direction of a recording medium such that the ribs are disposed to be different from one another, and disposing at least two rows on a platen along the conveying direction of the recording medium when the recording medium is conveyed onto the platen disposed to face a recording head for executing recording by discharging recording liquid droplets, and ink jet recording is performed, and performing recording except for recording data corresponding to each rib position, at each of at least the two rib rows when a recording operation is performed on a leading end or a rear end of the recording medium in the conveying direction thereof, thereby completing predetermined one-line recording.